Subprojectile having an energy content

ABSTRACT

The invention relates to a subprojectile ( 1 ) comprising a body, which is provided with a borehole ( 5 ) and consists of hard metal or heavy metal, an energy component ( 3 ) with or without a firing means ( 4 ) being incorporated into the borehole ( 5 ). The energy component ( 3 ) with or without a pressure-sensitive firing means ( 4 ) is fired or activated by air friction, by an ignition in the carrier bullet together with a firing charge, or at the latest when the target is hit.

This is a National Phase Application in the United States ofInternational Patent Application No. PCT/EP2008/002378 filed Mar. 26,2008, which claims priority on German Patent Application No. 10 2007 016828.6, filed Apr. 5, 2007 and on German Patent Application No. 10 2007021 451.2, filed on May 8, 2007. The entire disclosures of the abovepatent applications are hereby incorporated by reference.

FIELD OF THE INVENTION

The invention relates in particular to spin-stabilized submunitions of aprojectile which have an energetic content.

BACKGROUND OF THE INVENTION

It is known for incendiary compounds to be included as a fragmentationincendiary munition in a projectile body or explosive head together witha high explosive and in armour-piercing projectiles which do not containany explosive. In addition to fragments, the detonation or mechanicalfragmentation of the projectile or explosive head in or close to thetarget results in incendiary compound particles which fly at high speedand burn autonomously in the air. This results in a three-dimensionalincendiary effect which extends over a long time.

Known fragmentation incendiary munitions contain mixtures of highexplosives such as hexagon, octagon trotyl and aluminum powder.

DE 29 01 517 describes an incendiary compound having an organic binderand metal foam, for example composed of zirconium or hafnium, withpolytetrafluorethylene in a proportion of 2 to 15% by mass being used asthe binder.

EP 0 051 324 B1 from the same company, discloses an incendiary compoundof this generic type which uses an organic binder and metal particles.In order to lengthen the burning time, this solution proposes that metalpowder be used with a mean grain size of 15-50 μm. The binder, anorganic halogen-free binder, a polyvinylacetate, makes up a proportionof less than 2% by mass. This ensures that the metal powder can still becompressed adequately. The metal additive itself results in an increasein the blast effect and in lengthening of the flame life from 1 ms to 15ms. This increases the probability of ignition of combustible material.

Building on this incendiary compound, the further DE 10 2005 057 182 A1proposes the use of preferably spherical metal powder in the range50-250 μm.

The binder can therefore be used in the least possible concentrationwhich still ensures adequate compression capability and a fixing of theincendiary compound. The use of spherical metal powder, in particular ofzirconium metal powder, with a larger surface makes it possible for thebinder to be applied dry to the surface of the metal powder, thusincreasing the friability and allowing volumetric metering.

EP 1 286 129 A1 discloses a further incendiary charge for afin-stabilized kinetic-energy projectile which is highly effectivedespite having a relatively small volume and a low mass. The incendiarycharge is ignited by the shock waves created on impact with the target.A titanium foam is used, and epoxy resin or polyester resin is used asthe binder. The grain size range of the titanium foam is in this casearound 450 μm, with 30% having a grain size of more than 450 μm, and 70%having a grain size of less than 450 μm.

The invention is based on the object of achieving an incendiary effectwhich, in particular, is more effective in or on the target and causes areaction with energetic target material.

SUMMARY OF THE INVENTION

The object is achieved by the features of a first embodiment of theinvention, wherein a submunition (1), in particular arotation-stabilized submunition, has a body (2), which has a bore (5)and may be composed of hard metal or heavy metal, characterized in thatan energetic component (3) with or without igniter (4) is incorporatedin the bore (5).

Advantageous refinements of the first embodiment of the invention arespecified as follows. In accordance with a second embodiment of theinvention, the first embodiment is modified so that the energeticcomponent (3) is incorporated with the igniter (4) in the front or rearof the submunition (1). In accordance with a third embodiment of theinvention, the first or second embodiments are modified so thatpyrotechnic components with a thermobaric reaction are used as energeticcomponents (3). In accordance with a fourth embodiment of the invention,the third embodiment is further modified so that the energeticcomponents are, for example, zirconium powder, zirconium foam,thermites, pyrofuze or coruscative.

In accordance with a fifth embodiment of the invention, one of thefirst, second, third or fourth embodiments of the invention are furthermodified so that Mg, Al, Si-barium peroxide systems are used as anigniter (4). In accordance with a sixth embodiment of the invention, oneof the first, second, third, fourth and fifth embodiments of theinvention is further modified so that the energetic component (3) iseither pre-compressed in the bore (5) or is inserted in the bore (5). Inaccordance with a seventh embodiment of the invention, one of the first,second, third, fourth, fifth, and sixth embodiments is further modifiedso that the igniter (4) is metered and compressed. In accordance with aneighth embodiment of the invention, one of the first, second, third,fourth, fifth, sixth and seventh embodiments is further modified so thatthe energetic components (3) are fired or activated, with or withoutpressure-sensitive igniter (4), by the air friction that occurs,ignition in the carrier projectile together with an ejection charge, orat the latest on striking the target. In accordance with a ninthembodiment of the invention, one of the first, second, third, fourth,fifth, sixth, seventh or eighth embodiments is further modified so thatthe submunition is used in a projectile.

The invention is based on the idea of incorporating the incendiarycompound and the energetic component of a projectile in thesubmunitions. In a similar manner to that in the case of DE 10 2005 039901 A1, the submunitions are produced from ductile heavy metal or hardmetal in a known manner in a cylindrical, spherical or cuboid shape,with a cutout with or without weak points. The introduction andcompression processes then take place, preferably by machine, of theenergetic component and, if provided, the metering of apressure-sensitive ignition charge, with subsequent compression.

The submunitions can be released in a known manner.

The energetic content of the submunition is activated, depending on thedesign by:

-   -   ignition in the carrier projectile together with the break-up        charge (ejection charge),    -   ignition by air friction (ram-air pressure), or    -   ignition on striking the target.

The energetic content of the submunitions includes a pyrotechnic, suchas thermite, pyrofuze (c.f.,http:\\www.sigmundcohn.com/german/pyrofuse.html, DE 21 30 367 A1) orcoruscative (U.S. Pat. No. 3,135,205) with thermobaric reactions. Mg,Al, Si-barium per oxide-systems are used for the ignition pyrotechnics,for example, YIS 506 from the same company.

The submunitions are preferably spin-stabilized. The spin-stabilizeallows the submunition or submunitions to strike the target in anoriented manner. (Spin rate is approximately 1 000 Hz at the barrelmuzzle).

The orientation cavity with energetic content can be provided at thefront or rear in the submunition.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be explained in more detail using one exemplaryembodiment and with reference to the drawing, in which:

FIG. 1 shows a submunition illustrated from the side,

FIG. 1 a shows a section illustration A-A of a first variant of the formof the submunition shown in FIG. 1, and

FIG. 1 b shows a section illustration A-A of a second variant of theform of the submunition shown in FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION

With reference to a projectile as described in DE 10 2005 039 901 A1,this projectile may be adapted for use as a projectile in accordancewith the present invention, wherein the adapted projectile hassubmunitions 1 which have a hard-metal body and/or heavy-metal body 2,with a bore or recess 5, for holding an energetic component 3. Anigniter 4 preferably ends flat with the housing body 2.

The energetic component 3 may be a powder, a rod material, or the like.

In a first non-limiting embodiment of the invention, the zirconiumpowder is precompressed in the projectile bore 5, and the igniter 4 ismetered and is compressed to about 400 MPa. The ratio used for thispurpose may, in this case, be 10/1.

In a further non-limiting embodiment of the invention, pyrofuze is cutinto parts with a length of 8 mm, and is inserted into the projectilebore 5. In this case as well, the igniter 4 is metered and compressed. Aratio of 10/1 is also sufficient in this case, and it is been found tobe advantageous to use a ratio of 13/1.

If zirconium foam is used as in accordance with a third non-limitingembodiment of the invention, this is likewise precompressed in theprojectile bore 5, and the igniter 4 is metered. A ratio of 10/1 is alsorecommended in this case.

In a further, fourth, non-limiting embodiment of the present invention,the submunitions are compressed only with the corresponding energeticmaterials (zirconium powder, zirconium foam, pyrofuze, coruscative etc.)without an igniter in the projectile bore at about 400 MPa. The mass ofthe energetic compound can be increased, corresponding to the proportionresulting from the lack of the igniter.

The volume of the energetic material forced into the submunitions is inthe region of about 5-20% of the projectile volume.

The method of operation, in accordance with the invention, is asfollows:

The submunitions 1 of the carrier projectile, which is not illustratedin any more detail, are, for example, released by programmed triggering.The pyrotechnical energetic component 3 in the submunition 1 is fired byself-arming, or else by the pressure-sensitive igniter 4, which isignited by air friction, or ignition in the carrier projectile togetherwith an ejection charge, or at the latest on striking a target. Inaddition to its conventional function, this energetic component 3 nowalso has an incendiary compound and a reactive material, which reactschemically with target material in the target.

As indicated in FIG. 1 a and FIG. 1 b, the submunition may becylindrical or spherical, or else may have a polygonal cross section.

1. A submunition, in particular a rotation-stabilized submunition,comprises: (a) a body that which has a bore, wherein the body compriseshard metal or heavy metal; and (b) an energetic component, provided withor without an igniter, incorporated in the bore.
 2. The submunition asclaimed in claim 1, wherein the energetic component is provided with theigniter in a front portion or rear portion of the submunition.
 3. Thesubmunition according to claim 1, wherein the energetic componentcomprises pyrotechnic components fired with a thermobaric reaction. 4.The submunition as claimed in claim 3, wherein the energetic componentsare selected from the group consisting of zirconium powder, zirconiumfoam, thermites, pyrofuze and a coruscative.
 5. The submunition asclaimed in claim 2, wherein the igniter is selected from the groupconsisting of Mg, Al, Si-barium peroxide systems.
 6. The submunition asclaimed in claim 1, wherein the energetic component is eitherpre-compressed in the bore or is inserted in the bore.
 7. Thesubmunition as claimed in claim 2, wherein the igniter is metered andcompressed.
 8. The submunition as claimed in claim 2, wherein theigniter is a pressure-sensitive igniter, and the energetic component isfired or activated, with or without the pressure-sensitive igniter, byair friction that occurs, or by ignition in a carrier projectiletogether with an ejection charge, or at the latest by striking on thetarget.
 9. (canceled)
 10. The submunition according to claim 2, whereinthe energetic component comprises pyrotechnic components fired with athermobaric reaction.
 11. The submunition as claimed in claim 3, whereinthe energetic components are selected from the group consisting ofzirconium powder, zirconium foam, thermites, pyrofuze and a coruscative.12. The submunition as claimed in claim 2, wherein the energeticcomponent is either pre-compressed in the bore or is inserted in thebore.
 13. The submunition as claimed in claim 3, wherein the energeticcomponent is either pre-compressed in the bore or is inserted in thebore.
 14. The submunition as claimed in claim 4, wherein the energeticcomponent is either pre-compressed in the bore or is inserted in thebore.
 15. The submunition as claimed in claim 5, wherein the energeticcomponent is either pre-compressed in the bore or is inserted in thebore.
 16. The submunition as claimed in claim 11, wherein the energeticcomponent is either pre-compressed in the bore or is inserted in thebore.
 17. A projectile comprising a rotation-stabilized submunition,wherein the rotation-stabilized submunition comprises: (a) a body thathas a bore, wherein the body comprises hard metal or heavy metal; and(b) an energetic component, provided with or without an igniter,incorporated in the bore.